Positive-crowd mechanism



March 17, 1931. A. EILERSGAARD POSITIVE CROWD MECHANISM Filed May 25, 1928 2 Sheets-Sheet 1 yad/n" v 6122. fifa/Mins March 17, 1931. A. EILERSGAARD POSITIVE CROWD MECHANISM "Filed May 25, 1928 2 SheeLS-Sheer. 2

Patented Mar. 17, 1931 UNITED STATES PATENT OFFICE ASGEB EILERSGAARD, OF CHICAGO, ILLINOIS, ASSIGNOR TO LINK-BELT COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS IPOSITIVE-CROWD MEOHANISM Application led May 25,

My invention relates to improvements in positive crowd mechanism for shovels and the like and has for one object to provide in connection with a dipper shovel or eXca vatorhaving-a single source of power which o crates all the various mechanisms, a positive crowd and controlling means therefor. lA further object ofmy invention is to'provide in connection with .a shovel mechanism 1,0 and positive crowd therefor, new and imroved means for controllin and manipuating the shovel. Other objects of my invention will appear from time to time throughout the-specification and claims.-

My invention is illustratedmore or `less diagrammatically in `the Naccompanying drawings, wherein- Figure 1 is a side elevation; Figure 2 is a lan view. Like parts are indicated by like characters throughout the specification and drawings.

-A is a truck supported on idler rollers A1 A1 over which travel the endless crawler chains A2, there lbeing one on each side of the truck, this `chain bein driven by a sprocket A3. :A is a turn ta le on the truck associated with afixed swinging gear A5.

' A6 is a swinging or working platform being supported on the turn table A* by means of a series of rollers A7. A's is a pinion on the turn table A in mesh with the gear A5 whereby when the pinion is rotated the working platform A6 may be rotated on the truck.

B is a cab or housing mounted on the platform A. It contains preferably an internal combustion engine B1 which drives by means of a train of gears B2 Bs a drum shaft B4 mounted for rotation in the hoisting gear frame B5. Mounted on the drum shaft is a hoisting drum B", having at one end a clutch drum and clutch B'I whereby this hoisting drum may be connected to and disconnected from the'drum shaft B* for driving. On the other end of the drum B1 is a brake and brake drum .B8 whereby rotation of the hoisting drum may be controlled. On 'the same shaft B* is a crowd drum B9 associated with a brake and brake drum B1o and with a clutch and clutch drum B11 whereby the 192s. Serial No. 280,430.

crowd drum B9 may be driven in the same direction as the shaft B4.

C is a reversing shaft mounted for rotation in the hoisting gear frame B5. Rigidly mounted on the shaft C- is a sprocket C1 over which travels a sprocket chainv C2 which chain also travels over a sprocket Cs rigidly mountedon the drum B9 so that the shaft C and the drum B always rotate in unison. C* is a gear rigidly mounted on .the shaft B4 and in mesh with a gear C5 on the shaft C. C is a clutch and clutch drum' interposed between the gear C5 and the shaft C so that the gears C4 and C5 always rotate in unison with the shaft B4. There being one gearon each shaft, obviously when the shaft B4A is driven through the chain, it travels in one direction and when driven through the gears it travels in the opposite direction. C7 is a sprocket on the shaft C over which travels a chain Cs which chain also travels vover a sprocket C9, this chain bein held tight by means of an idler sprocket 1 pivoted on the lever C11 and adJusted by means of a turn buckle and screw C12.

Projecting forwardly from the front edge of the platform A6 on opposed ends thereof are brackets D. These brackets carry pins D1 upon which are pivoted yokes D2, which yokes i are attached to the inner end of the boom D3, the boom being tapered so as to be wider at its lower end where it is pivoted on the working platform, than it is at the upper end. D4 is a shipper shaft mounted for rotation on and extending transversely across the boom DS. This boomns centrally apertured as at D5 to permit longitudinal travel of the dipper handle or stick D8. A bridle D7 pivoted on the shaft Dtin which the dipper handle is slidably mounted furnishes a floating pivot for the dipper handle. D8 is a shipper rack extending along that'side of the handle ad- E3 and the sprockets E2 and C9 though the axis of rotation of all three of them are on the same line.

F is a dipper bucket mounted on the end of the boom D6. It has the usual pivoted floor or bottom F1 and cutting teethF2 and is equipped with a pivoted yoke F3. Extending upwardly from this yoke is a cable F4 to pass up over a sheave F5 at the end of the boom and thence down about the hoi-sting drum B8. F'is an A-frame projecting upwardly from the working platform A6'. F7 are cables extending from the A-frame around sheaves Fs and thence back over sheaves F9 on the A- frame F6 and thence down to a drum F10 whereby the boom may be supported and thel angle vof the boom controlled though as a igleneral proposition the boom remains at a xed angle during operation.

' vThe use and operation of my invention are as follows:

The motor drives the drum shaft through the train of gears indicated and this drum shaft always rotates in the same'direction. When the operator wishes to operate the bucket, he manipulates the clutch to cause the drum shaft to rotate the drum to raisev the bucket. When the bucket is raised, he can either hold it by the brake and throw out the clutch or throw out the clutch and let it drop but gravity does'the work., There is no need of any reversing mechanism in connection with the dipper or bucket hoist.

Since the gear on the drum'shaft is; rigid thereon, it always turns with it and turns the other gear on the reversing shaft, therefore these two gears are always in rotation. The chain leading from the sprocket on the drum shaft to and aroundvthe sprocket onthe reversing shaft is connected to the drum shaft by the clutch associated with the drum lals sprocket. Only when this clutch is engaged is this sprocket chain driven by the drum shaft. All other times it idles with the reversing shaft. The clutches controlling the sprocket chain and controlling the two gears are soarranged that when one is in, the other is out though they both may be out and neutral at the same time.- Thus a manipulation of the control lever will cause .thereversing shaft to rotate in either a forward or reverse directionhin response to rotation of the drum shaft. The driving connection between the reversing shaft' and the sprocket concentric with the boom and between such s' rocket and the shipper shaft is of course o vious. The two clutches may be manipulated to drive the shipperl shaft in either direction'and thus to crowd oit or retract the boom as the case may be.

I-claim:

l. In an excavating machine, a working platform, a boom pivoted thereon at two widely spaced points, a dipper handle slidable in the boom, a dipper shaft associated therewith to drive it, a jack shaftinterposed between and concentric with the two pivot connections of the boom on the working platform, a sprocket and chain drive interposed between the shipper shaft and the jack shaft and means for driving the jack shaft.

2. In: an excavating machine, a working platform, a boom pivoted thereon at two widely spaced points, a dipper handle slidable in the boom, a dipper shaft associated therewith to drive it, a jack shaft interposed between and concentric with the two pivot connections of the boom on the working platform, a sprocket and chain drive interposed between the shipper shaft and the jack shaft and-means for driving the jack shaft, said means comprising a reversing shaft, a.

sprocketu and chain connection between it and the jack shaft and means interposed between the working shaft and the motor for driving it selectively in opposite directions.

3.' In. an excavating machine, a working platform, a boom pivoted thereon, the pivot connection between the boom and platform comprisingseparate spaced brackets on boom` and platform, pivot pms one for each pair of brackets to hold the brackets on boom and platform together, a dipper handle slidable and rotatable on the boom, a shipper shaft associated therewith, a'jack shaft on the platform concentric with the pivot axis of the boom and a sprocket and chain connection between the jack shaft and the shipper shaft.v

4.111 an excavating machine, a working platform, a boom pivoted thereon, the pivot connection between the boom and platform f comprising separate spaced brackets on boom and platform, pivot pins one for each pair of brackets to hold the brackets on boom and lplatform together, a dipper handle slidable and rotatable on the boom, a shipper shaft associated therewith, a jack shaft on the platforml concentric with the pivot axis of the boom and a sprocket and chain connection between the jack shaft and the shipper shaft, the jack shaft being located between the two points where the boom is pivoted on the platform. v

5. In an excavating machine, a working platform, a boom pivotedthereon, the pivot connection between lthe boom andplatform comprising separate spaced brackets on boom and platform, pivot pins one for each pair iso v and rotatable on the boom,

of brackets to hold the brackets on boom and platform together, a dpper handle slidable and rotatable on the boom, a shipper shaft associated therewith, a jack shaft on the latrform concentric with the pivot axis o the boom and a sprocket and chain connection between the jack shaft and the shipper shaft, the jack shaft being in line with between but altogether out of contact with the two pivot shafts. 6. In an excavating machine, a working platform, a boom pivoted thereon, the pivot connection between the boom and platform comprising separate spaced brackets on boom and platform, pivot pins one for each pair of brackets to hold the brackets on boom and platform together, a dipper handle slidable a shipper shaft associated therewith, a-j ack shaft on the platform concentric with the pivot axis of the boom and a sprocket and chain connection between the jack shaft and the shipper shaft, the jack shaft being-located between the two points where the boom is pivoted on the platform, driving means for the jack shaft including a reversing shaft.

y7. In an excavating machine, a working platform, a boom pivoted thereon, the ivot connection between the boom and plat orm comprising separate spaced brackets on boom and platform, pivot pins one for each pair of brackets to hold the brackets on boom and platform together, a dipper handle slidable and rotatable on the boom, a shipper shaft associated therewith, a jack shaft on the platform concentric with the pivot axis of the boom and a sprocket and'chain connection between the jack shaft and the shipper shaft, the jack shaft being in line with, between but altogether out of contact with the two ivot shafts, driving means for the jack sha including a reversing shaft.

8. A hoistin mechanism for excavating machines and t e likev comprising a supporting frame, a drum shaft, and means for positively driving it, a pair of drums rotatable on the shaft, a hoisting cable wound about one of said drums, a sprocket mounted `on the other, clutches and brakes associated'with each of the drums whereby each drum may be separately driven from the drum shaft, a reversing shaft parallel with the drum shaft, a' gear train interposed between the drum shaft and the reversing shaft, a s rocket on the reversing shaft and an en ess chain driven over both said sprockets, clutches associated with the gear train and the sprocket and chain train whereb the reversing shaft may be driven selective y in either direction by the drum shaft, and may be disconnected therefrom.

Signed at Chicago, county .of Cook, and State of Illinois this 21st day of Ma 1928. l AsGER EILERsG D. 

